The present invention relates to a pickup in an optical disk player and, more particularly, to a pickup adjusting apparatus which enables fine adjustments to the tilt of a pickup so that the pickup can be maintained horizontal with respect to a disk.
In an optical disk player such as a CDP (compact disk player), an LDP (laser disk player) or a DVDP (digital video disk player), a pickup should be maintained horizontal with respect to a disk so that a laser beam emitted from the pickup is vertically incident on the disk.
FIG. 1 illustrates the pickup portion of a typical disk player. As shown in the drawing, a turntable 1 for receiving a disk (not shown) and a pair of guide shafts 2 for supporting a pickup 3 are installed on a deck 4. To one side of the pickup 3, a tooth gear portion (not shown) for engaging with a screw shaft 5 is formed. The screw shaft 5 is driven by a driving motor 6.
In the disk player having the above structure, when the driving motor 6 rotates the screw shaft 5, the rotation of the screw shaft 5 slides the pickup 3 along the guide shafts 2. Accordingly, as the pickup 3 moves in a radial direction of the disk, information recorded on the disk is read by the pickup 3.
When reading information from the disk, the laser beam emitted from the pickup 3 should be perpendicularly incident on a desired position on the disk. However, pickup errors, due to a focusing error or an inclination error of the pickup 3, sometimes occur. The focusing error occurs when the laser beam does not appropriately converge on the disk according to the distance between the disk and the pickup 3. The inclination error occurs when the pickup 3 is inclined in a radial direction or a tangential direction with respect to the disk. Such errors can be compensated for by the focusing and tracking servo mechanism of the pickup 3, but only to a limited degree since the guide shafts 2, which support the pickup 3, are fixedly mounted to the deck 4 by fixing portions 7 during the assembling process. Thus, complete compensation for the errors may not be possible. Further, in the case where accuracy is low during assembly and there is a large tolerance, correction for the above-mentioned errors becomes impossible.
To solve the above problems, it is an object of the present invention to provide a pickup adjusting apparatus in an optical disk player which enables fine adjustment to the tilt of a pickup to thereby correct inclination errors in a radial direction of a disk.
Accordingly, to achieve the above object, there is provided a pickup tilt adjustment apparatus in a disk player which includes a deck and a pickup. The pickup adjusting apparatus includes at least one pair of guide shafts installed on the deck and for supporting and guiding the pickup. Each of the guide shafts has a hole at least one end thereof, an adjusting means inserted into each hole and threadedly engaged with the deck, and a spring installed between each of the guide shafts and the deck and for providing a resistive force against a rotation of the adjusting means and biasing the guide shafts away from the deck, thereby to maintain an appropriate distance between the deck and each of the guide shafts.